1. Field of the Invention
The present invention relates to a consumable electrode type pulse arc welding method by which welding is conducted in such a manner that at least one of the welding current and the welding voltage is superimposed like pulses between a welding wire and a welding base metal (work).
2. Description of the Related Art
Conventionally, in this type pulse arc welding method, an arc of pulse arc welding is started by using the same pulse parameter as that of main welding from the start of welding.
However, when an arc of welding is started by the same pulse parameter as that of main welding, short circuit is irregularly caused because of an unstable arc at the start of arcing. Due to the foregoing, a period of time of short circuit is extended, and big pieces of spatter are generated, or the arc is suddenly cut off. Further, a change in the welding current per unit time at the rise and fall of pulses is so sharp that a value of the change is .+-.1000 to 1400 A/msec. Therefore, a magnetic arc blow occurs, and the arc becomes unstable. Accordingly, it is impossible to form proper welding beads.